The Headers and Response constructors combine duplicate entries (a: x,
a: "") into one value with the separator, which can end in its space
("x, "). They marked the pairs canonical anyway, so a copy took them
unchanged where Node trims the copied value ("x,"). The constructors
now mark the pairs canonical only when every value is already trimmed;
otherwise copies normalize them pair by pair.
Appending an empty value to an existing header leaves the separator's
space at the end of the combined value ("x, "). Node keeps that in the
Headers object but trims it when the value is copied into another
Headers, Request or Response ("x,"). The copy fast path copied a
canonical object's pairs as they were, so the copy kept the space. Such
an append now marks the pairs as no longer canonical, and copies
normalize them pair by pair.
Headers kept its name/value pairs in a string array and read every element
through scr_arr_get_ref (index checks, retain, release). forEach and the
iterators re-sorted and rescanned the whole list for every step, and every
Response or Headers built from another Headers object re-validated and
re-normalized each copied pair. The Hono fixture spends 12-15% of a request
there.
- Pair loops read borrowed elements of the dense array (sf_pair_at).
- The sort-and-combine list is cached on the Headers object and dropped by
every mutation, so live iteration keeps Node's semantics.
- get() of a single value returns the stored string.
- Copying a Headers object whose pairs are canonical (built by the
constructor or a Response) into an empty list copies the pairs; wire
response headers keep the per-pair path because they may repeat names.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Chris Tate